The present invention is particularly designed for use as a compact, automatic purified water distillation unit of the type especially adapted for home use to produce 4-6 gallons, more or less, drinking water per day for an average sized family. The unit is also especially adapted for relatively small office use to take the place of bottled water stands as may be found in many offices as well as residential homes.
The unit embodying the present invention may be designed for home installation under a conventional kitchen sink, along with required utility connections including electrical, feed water supply, and waste water drainage. The unit may be plumbed to supply the distilled water to a dedicated faucet installed faucet at the sink, and also to supply distilled water to the inlet of an ice-making machine such as located in the freezer department of a conventional refrigerator, or the like.
In addition to home installations, a unit embodying the invention is extremely well suited for desalination of sea water in marine applications and/or purification of any water in industrial as well as other applications outside the home. Depending on distilled water needs in terms of volume, a unit embodying this invention may be scaled up or down to produce anywhere from a few gallons a day to thousands of gallons per hour.
Numerous functional advantages are obtainable using the present distillation system including:
1) The closed circuit component above-mentioned, creates a partial vacuum in the evaporator so that feed-water supplied to said evaporator can be heated to boiling point and converted to steam at below atmospheric boiling point (which at sea level is 212.degree. F.). The boiling of water at lower temperatures prevents scale buildup on the heating elements and heat transfer surfaces installed in the evaporator tank. The building up of scale is perhaps the singularly most inconvenient and annoying part of standard systems where boiling is at atmospheric pressure and at higher temperatures. Scale buildup reduces the efficiency of the heat transfer from the heating elements to the surrounding water and must be cleaned out on a regular basis with acid to prevent massive scale buildup which will stop the distillation process and cause heater failure. PA1 2) A second benefit of operating at lower temperatures is that it allows the use of plastics, rather than more expensive and difficult to work with metals, in various components where feasible. PA1 3) The present unit is both fully automatic and is water cooled (air cooling is optional). Most home size distillers are batch operations, and are not automated. The consumer must monitor the quantity of water in storage, drain the evaporator, refill the evaporator and start the distiller when more water is required. Another negative aspect of more conventional home distillers is that the steam condenser coils are usually air-cooled instead of water-cooled. Thus, all of the heat from the process is air blown into the room to raise the overall room temperature which can be obviously undesirable, especially in hot climatic conditions. PA1 4) An "under the sink" unit embodying the present invention can be produced and marketed at cost competitive with or lower than the cost to a home owner of using bottled water, with its multiple attendant disadvantages of requiring the heavy lifting of full bottles into inverted positions in the water dispensing stand as well as putting up with the clutter and wasted floor space used by the dispenser and full and empty bottles.
Other objects and advantages of the invention will become apparent upon reading the following specification and referring to the accompanying drawings.